About Lung Cancer

Lung cancer is typically classified by their different cell structures when examined under a microscope.
  • Non-small cell lung cancer: is the most common type of lung cancer, representing approximately 85% of lung cancers. Non-small cell lung cancer has three main subtypes:
    • Adenocarcinoma: Adenocarcinoma, which begins in cells that line the alveoli, is the most common type of lung cancer. While this type of lung cancer occurs mainly in current or former smokers, it also is the most common type of lung cancer seen in non-smokers. It is more prevalent in women than in men and is more likely than other types of cancer to occur in younger people.
    • Squamous cell (epidermoid) carcinoma: Representing approximately 25 to 30 percent of all lung cancers, squamous cell carcinoma begins in thin, flat cells that line the bronchial tubes in the center of the lungs, near a bronchus. It is most often caused by tobacco smoking.
    • Large cell (undifferentiated) carcinoma: Large cell carcinoma, which can start anywhere in the lungs, is almost always associated with smoking.
    • Other subtypes: Other forms of non-small cell lung cancer are rarer and include adenosquamous carcinoma, carcinoid (well-differentiated neuroendocrine tumor) and sarcomatoid carcinoma.
  • Small cell (oat cell) lung cancer: This type of lung cancer makes up about 15% of lung cancers and almost always is caused by tobacco smoking. It tends to grow quickly and spread widely to other parts of the body fairly early in the course of the disease, but often responds well to chemotherapy.
  • Pulmonary metastases: Sometimes tumors found in the lungs are not lung cancer at all, but a cancer from another organ that have spread to the lungs. These are identified by their primary cancer type. The most common cancers resulting in pulmonary metastases include breast, colorectal and kidney cancers.
Each type of lung cancer grows and is treated in different ways. Your City of Hope team of lung cancer experts will carefully study your individual case and work with you to determine the best treatment plan for you. Learn more about our approach to diagnosis and staging.
Signs and Symptoms of Lung Cancer
Symptoms of lung cancer can include:
  • a cough that worsens or does not go away
  • breathing trouble, such as shortness of breath
  • constant chest pain, worsened by deep breathing, coughing or laughing
  • coughing up blood or rust-colored spit
  • persistent hoarseness
  • frequent lung infections, such as pneumonia or bronchitis
  • swelling of the neck and face
  • arm or shoulder pain
  • ongoing fatigue
  • loss of appetite or unexplained weight loss

Early lung cancer detection is critical to successful treatment, so if you or a loved experience any of the above symptoms, please contact a doctor for further evaluation.
Lung Cancer Risk Factors
  • Smoking: Tobacco smoking is by far the most important risk factor for lung cancer, causing 90 percent of cases in men and about 80 percent of cases in women. Cigarette, pipe and cigar smoking all add to the risk of lung cancer. Low tar or nicotine cigarettes do not lower that risk.
  • Secondhand smoke: People exposed to secondhand tobacco smoke are also at a higher risk of developing lung cancer. People who breathe in the smoke exhaled by smokers are exposed to cancer-causing agents.
  • Radon exposure: Exposure to radon, a radioactive gas, can increase the risk of lung cancer. A product of uranium breakdown, radon can come up through the ground and leak into buildings. Of nonsmokers killed by lung cancer, about 30 percent had been exposed to radon.
  • Family history: A person with a family member who has had lung cancer may be at an increased risk of developing the disease.
  • Exposure to other substances: Exposure to substances such as asbestos, arsenic, diesel exhaust and some forms of chromium are linked to a higher lung cancer risk.
If you suspect that you or a loved one may have an elevated risk of lung cancer, please consult with a doctor on preventive and early detection measures that are available.
If you have been diagnosed with lung cancer or are looking for a second opinion consultation about your treatment, find out more about  becoming a patient or contact us at 800-826-HOPE.
Sources: American Cancer Society, National Cancer Institute and Centers for Disease Control and Prevention